首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9553篇
  免费   686篇
  国内免费   21篇
耳鼻咽喉   71篇
儿科学   322篇
妇产科学   334篇
基础医学   1355篇
口腔科学   169篇
临床医学   1001篇
内科学   1747篇
皮肤病学   206篇
神经病学   1065篇
特种医学   344篇
外科学   930篇
综合类   79篇
一般理论   15篇
预防医学   1005篇
眼科学   138篇
药学   632篇
中国医学   10篇
肿瘤学   837篇
  2023年   117篇
  2022年   199篇
  2021年   338篇
  2020年   240篇
  2019年   326篇
  2018年   310篇
  2017年   257篇
  2016年   265篇
  2015年   279篇
  2014年   369篇
  2013年   478篇
  2012年   726篇
  2011年   661篇
  2010年   342篇
  2009年   336篇
  2008年   519篇
  2007年   525篇
  2006年   459篇
  2005年   444篇
  2004年   374篇
  2003年   336篇
  2002年   313篇
  2001年   141篇
  2000年   121篇
  1999年   112篇
  1998年   74篇
  1997年   50篇
  1996年   57篇
  1995年   34篇
  1994年   46篇
  1993年   51篇
  1992年   79篇
  1991年   73篇
  1990年   62篇
  1989年   69篇
  1988年   61篇
  1987年   72篇
  1986年   83篇
  1985年   97篇
  1984年   71篇
  1983年   56篇
  1982年   33篇
  1981年   36篇
  1980年   37篇
  1979年   46篇
  1978年   36篇
  1977年   35篇
  1976年   38篇
  1975年   37篇
  1972年   34篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases.  相似文献   
2.
3.
4.
5.
OBJECTIVE: To evaluate the prenatal distribution, associated conditions and outcome of the different types of right aortic arch (RAA) detected in fetal life. METHODS: This was a retrospective review of all cases of RAA detected prenatally between 1998 and 2005 in two tertiary referral centers. RESULTS: In the study period 71 cases of RAA were detected; 26 (37%) had RAA with aberrant left subclavian artery, 23 (32%) had RAA with mirror-image branching, 20 (28%) had RAA of unknown type and two (3%) had double aortic arch. While 20/26 cases with RAA and aberrant left subclavian artery were isolated findings, all 23 cases with RAA and mirror-image branching were associated with cardiac defects, namely tetralogy of Fallot (43%) or pulmonary atresia with ventricular septal defect (22%). Of the 20 cases with RAA, 19 of unknown type were associated with heterotaxy syndromes and had additional cardiac malformations and ambiguities of the situs. The two cases with DAA were isolated findings. Seven cases in our series (10%) had a microdeletion 22q11 and these were significantly associated with extracardiac malformations. The outcome in our series depended solely on the associated cardiac and extracardiac malformations, with the exception of one infant with isolated DAA, in whom a surgical correction was warranted. CONCLUSIONS: RAA detected in fetal life is associated frequently with other cardiac/non-cardiac malformations, heterotaxy syndromes and microdeletions 22q11. The associated conditions vary depending on the branching type of the brachiocephalic vessels and the presence of extracardiac malformations.  相似文献   
6.
7.
The objectives of this study were to systematically review and meta-analyze the research literature on the association of common neurological disorders and violence. Keywords relating to neurological disorders and violence were searched between 1966 and August 2008. Case–control and cohort studies were selected. Odds ratios of violence risk in particular disorders compared with controls were combined using fixed-effects meta-analysis with the data presented in forest plots. Sensitivity analyses were conducted to identify possible differences in risk estimates across surveys. Information on risk factors for violence was extracted if replicated in more than one study. Nine studies were identified that compared the risk of violence in epilepsy or traumatic brain injury compared with unaffected controls. For the epilepsy studies, the overall pooled odds ratio for violent outcomes was 0.67 [95% confidence interval (CI) 0.46–0.96]. For traumatic brain injury, the odds ratio was 1.66 (95% CI 1.12–2.31). An additional 11 case–control studies investigated factors associated with violence in epilepsy and traumatic brain injury. It was not possible to meta-analyze these data. Comorbid psychopathology was associated with violence. Data on other neurological conditions was limited and unreplicated. In conclusion, although the evidence was limited and methodological quality varied, epilepsy and traumatic brain injury appeared to differ in their risk of violence compared with control populations. Longitudinal studies are required to replicate this review’s provisional findings that epilepsy is inversely associated with violence and that brain injury modestly increases the risk, and further research is needed to provide information on a broader range of risk factors.  相似文献   
8.
To explore the concept of the young adult chronic patient as a distinct clinical entity, the author analyzed a sample of 134 chronic patients on six variables relating to style of interaction with service providers and on diagnostic and demographic variables. The results showed that the 105 younger chronic patients in the sample were more likely than the older patients to be male, to be referred to treatment for suicidal and homicidal gestures and ideation, to have a diagnosis of personality disorder, and to be overrepresented in the treatment population. The author believes the combination of these factors helps create disproportionately high visibility for young adult chronic patients and requires special provisions for their engagement in treatment.  相似文献   
9.
Twenty-five patients with primary presentation of malignant astrocytoma, astrocytoma with anaplastic foci, and glioblastoma multiforme were treated with surgical resection and definitive radiation therapy followed by intravenous or intra-arterial administration of Iodine-125 labeled monoclonal antibody-425, which binds specifically to human epidermal growth factor receptor. The patients presented with primary untreated disease, positive contrast enhanced computed tomography scans of the brain, and compatible clinical symptoms. In this Phase II clinical trial, the patients had surgical debulking or biopsy followed by definitively administered external beam radiation therapy and one or multiple doses (35 to 90 mCi per infusion) of radiolabeled antibody. The total cumulative doses ranged from 40 to 224 mCi. The administrations of the radiolabeled antibody were performed in most cases 4-6 weeks following completion of the primary surgery and radiation therapy. Ten patients had astrocytoma with anaplastic foci and 15 had glioblastoma multiforme. No significant life-threatening toxicities were observed during this trial. At 1 year 60% of the patients with astrocytoma with anaplastic foci or glioblastoma multiforme are alive. The median survival for both groups was 15.6 months.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号